Johannesburg emergency medical services spokesperson Robert Mulaudzi said they responded to the fire, inside an abandoned building in the township.
On their arrival, firefighters found 50 shacks on fire.
Maludzi said 30 of the shacks were inside the building while 20 others were outside.
The cause of fire is unknown and they are investigating.
However, residents told The Citizen the power was off due to load reduction in Johannesburg, and when the power returned, the fire started.
This is a developing story.
(Compiled by Carina Koen)